The invention is directed to a method and apparatus for controlling the ripening of fresh produce, particularly fresh fruit such as bananas.
Bananas and other fresh produce are typically transported from the growing fields to a processing facility where they are placed in specially designed ripening rooms. Such ripening rooms are provided with insulated, gas tight wall and roof panels and include an air handling unit to control the circulation and temperature of the air within the ripening room. In this manner, the ripening of the fresh produce may be controlled in accordance with a predetermined ripening schedule such that the fruit is properly ripened at the time it is scheduled for delivery to retail outlets. To advantage, ethylene gas is dispersed into the room at a preselected time to facilitate a uniform ripening of the produce. Accordingly, the use of ripening rooms enables the delivery of high quality produce to retail outlets without the constraint of having to schedule delivery in accordance with the natural ripening process of the fruit and further obviates problems associated with accelerations and decelerations of the ripening process due to changing conditions during the transportation of the produce.
In one advantageous prior ripening room arrangement, the produce is packed into unitized shipping modules comprising individual protective boxes which are block-stacked on pallets. The palletized produce is inserted into a ripening chamber having a floor, ceiling and front, rear and side walls and being of suitable dimensions to enclose two spaced rows of the
palletized produce. The two rows are spaced apart from one another within the chamber to define an intersitial volume between the rows which substantially forms a low pressure plenum. There is also provided sufficient spacing between the palletized produce and the ceiling and walls of the chamber to define a high pressure air space around and above the inserted produce load.
A tarp arrangement is placed over the top and one end of the spacing between the two rows of palletized produce to seal off the low pressure plenum from the high pressure air space. Exhaust fans are arranged in a sealed relation at the opposite end of the spacing between the rows to withdraw air from the spacing and thereby create a pressure differential between the tarp sealed plenum and the high pressure air space. The air introduced by the air handling unit is forced by the pressure differential between the high pressure air space and the low pressure plenum to flow through openings formed in the sides of the boxes, around the produce contained therein and into the low pressure plenum to be exhausted by the fans. In this manner, a forced air circulation is caused to flow uniformly throughout the produce load in the chamber to thereby uniformly control the temperature of the produce with a minimal temperature differential throughout the produce load. The temperature and flow rate of the air introduced into the chamber by the air handling unit may be accurately controlled to achieve a desired ripening rate for the produce.